:root {
    /* 亮色主题 */
    --primary-color: #ececec;
    --secondary-color: #3f37c9;
    --success-color: #2ecc71;
    --warning-color: #f1c40f;
    --danger-color: #e74c3c;
    --background-color: #f8f9fa;
    --surface-color: #ffffff;
    --text-color: #2c3e50;
    --border-color: #7ecbf1;

    /* 暗色主题 */
    --dark-primary: #7289da;
    --dark-secondary: #5865f2;
    --dark-background: #36393f;
    --dark-surface: #2f3136;
    --dark-text: #ffffff;
}

/* 基础样式 */
body {
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    transition: all 0.3s ease;
}

body.dark-theme {
    background-color: var(--dark-background);
    color: var(--dark-text);
}

/* 顶部导航栏 */
.top-navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 70px;
    background: var(--surface-color);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 2rem;
    z-index: 1000;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.logo {
    height: 40px;
    width: auto;
}

.brand-name {
    font-size: 1.5rem;
    font-weight: 600;
}

.nav-tools {
    display: flex;
    align-items: center;
    gap: 2rem;
}

/* 搜索框 */
.search-box {
    position: relative;
    width: 300px;
}

.search-box input {
    width: 100%;
    padding: 0.8rem 1rem 0.8rem 2.5rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    transition: all 0.3s ease;
}

.search-box i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: #666;
}

/* 主容器 */
.main-container {
    display: flex;
    margin-top: 70px;
    min-height: calc(100vh - 70px);
}

/* 侧边栏 */
.sidebar {
    width: 280px;
    background: var(--surface-color);
    padding: 2rem;
    border-right: 1px solid var(--border-color);
}

.menu-section {
    margin-bottom: 2rem;
}

.menu-section h3 {
    font-size: 0.9rem;
    color: #666;
    margin-bottom: 1rem;
    padding-left: 0.5rem;
}

.menu-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.menu-item {
    display: flex;
    align-items: center;
    padding: 1rem;
    margin-bottom: 0.5rem;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.menu-item i {
    margin-right: 1rem;
    width: 20px;
    text-align: center;
}

.menu-item:hover {
    background: rgba(67,97,238,0.1);
    color: var(--primary-color);
}

.menu-item.active {
    background: var(--primary-color);
    color: white;
}

/* 主要内容区 */
.main-content {
    flex: 1;
    padding: 2rem;
}

/* 欢迎卡片 */
.welcome-card {
    background: var(--surface-color);
    border-radius: 15px;
    padding: 2rem;
    margin-bottom: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.welcome-text h1 {
    margin: 0;
    font-size: 2rem;
    font-weight: 600;
}

.quick-actions {
    display: flex;
    gap: 1rem;
}

.action-btn {
    padding: 0.8rem 1.5rem;
    border: none;
    border-radius: 8px;
    background: var(--primary-color);
    color: white;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.action-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(67,97,238,0.2);
}

/* 统计卡片 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--surface-color);
    border-radius: 15px;
    padding: 1.5rem;
    display: flex;
    align-items: center;
    gap: 1.5rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 15px rgba(0,0,0,0.2);
}

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    background: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
}

.stat-icon i {
    font-size: 1.8rem;
    color: white;
}

/* 最近活动 */
.recent-activities {
    background: var(--surface-color);
    border-radius: 15px;
    padding: 2rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.activity-list {
    margin-top: 1.5rem;
}

.activity-item {
    display: flex;
    align-items: start;
    gap: 1rem;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
}

.activity-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(67,97,238,0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-color);
}

.activity-content h4 {
    margin: 0;
    font-size: 1rem;
    font-weight: 600;
}

.activity-time {
    font-size: 0.875rem;
    color: #666;
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .sidebar {
        width: 80px;
        padding: 1rem;
    }

    .menu-item span,
    .menu-section h3 {
        display: none;
    }

    .menu-item i {
        margin: 0;
        font-size: 1.2rem;
    }
}

@media (max-width: 768px) {
    .nav-brand .brand-name,
    .search-box {
        display: none;
    }

    .welcome-card {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
    }

    .quick-actions {
        width: 100%;
    }

    .action-btn {
        flex: 1;
    }
}